This invention relates to the construction of double insulated windows as well as to retrofitting of an existing single pane or window into a dual or multiple insulated panes.
A large percentage of the energy lost through the walls of a building in the winter is lost through the window panes. Accordingly, it is desirable to install insulated or thermal windows where possible. Because of the present cost it is extremely expensive to fabricate a double pane insulated window particularly of large dimensions and then install them at remote locations. The present invention has the unique ability to permit the installation of a single pane and thence with the application of a sealant spacer at the site permits the further installation of a second pane immediate over the first pane or window to provide a double insulated window. This is particularly significant in industrial and office structures.
Another method of dealing with the problem of heat loss through windows is to replace existing panes with insulated panes or the placement of a storm window thereon to provide thermal insulation of windows which cuts down on the transmission of heat to a substantial extent. The use of a supplemental window sash placed on the exterior of the conventional window sash during the winter months has the disadvantage of requiring annual removal with the accompanying interference with ventilation at the end of a season as well as at the beginning of the cold season. Further such supplemental windows are impractical for the larger home panes or industrial and office structural panes.
The present invention overcomes these disadvantages of conversion or retrofitting by providing a permanent dual pane installation without requiring removal of existing panes. The present invention is particularly useful in industrial and office structures and even in high rise or large type apartment dwellings which employ large picture windows. The present invention permits the economic retro-fitting of existing panes by adding a pane into the existing pane with proper spacing and sealing means to insure a sealed insulated space therebetween. The present invention permits this economical and aesthetic method for installation of insulated panes even where access to the exterior panes is virtually impossible.